<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<style>
  #send-btn{
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100vh;
  }

  button {
    border: 0;
    padding: 10px 30px 10px 20px;
    border-radius: 5px;
    color: white;
    font-weight: bold;
    /* text-transform 属性控制文本的大小写。uppercase  lowercase  capitalize(仅大写开头)*/
    text-transform: uppercase;
    background: #5f55af;
  }

  button svg {
    display: inline-block;
    vertical-align: middle;
    padding-right: 5px;
  }

  button:hover svg {
    animation: fly 2s ease 1;
  }

  @keyframes fly {
    0% {
      transform: translateX(0%);
    }

    50% {
      transform: translateX(300%);
    }

    100% {
      transform: translateX(0);
    }
  }

</style>
<body>
  
  <div id="send-btn">
    <button>
      <!-- 这里是一个svg的占位 -->
      send
    </button>
  </div>
</body>
</html>